Technical Field
The present invention relates to semiconductor processing, and more particularly to devices and methods with self-aligned contacts formed using a subtractive etch to reduce contact resistance.
Description of the Related Art
Middle of the line (MOL) resistance characteristics have become one of the dominant performance detractors in scaling of semiconductor devices. Current solutions require significant material changes and materials research to attempt to reduce the contact resistance in MOL structures. One issue includes the increasing proportion of metal lines (higher resistivity) to bulk metals (lower resistivity) in vias. Many designs still employ contact liners in a 1×1 square via, which is most negatively impacted by the contact liners.